Feeding mechanism for sewing machines



June 29, 1954 A. J. MATU ZAS 2,632,243

FEEDING MECHANISM FOR SEWING MACHINES Filed July 30, 1952 INVENTOR.Anthony lMaiugas W1TNE8S= BY ATTORNEY Patented June 29, 1954 FEEDINGMECHANISM FOR SEWING MACHINES Anthony J. Matuzas, Union, N. J assignorto The Singer Manufacturing Company,

Elizabeth,

N. J a corporation of New Jersey Application July 30, 1952, Serial No.301,644

9 Claims. 1

This invention relates to sewing machines and more particularly toimprovements in feed-dog throw-out devices especially adapted for usewith family-type sewing machines. Feed-dog throwout devices are designedto inactivate the workfeeding mechanism of sewing machines when it isdesired to use the sewing machine for darning, embroidering and othersimilar operations, and to reactivate the feeding mechanism when themachine is to be used for ordinary sewing operations.

The present invention is adapted for use with the feed-dog throw-outdevice which is the subject of a patent application of Josef F. Palmeand Jacob B. Benzing, Serial No. 222,616, filed April 24, 1951, and thepresent invention has for its primary object the provision of animproved feed-dog throw-out device.

Another object of the invention is to provide a feed-dog throw-outdevice which is easy to operate and which is positive in its action.

A further object of the invention is to provide a feed-dog throw-outdevice which when adjusted for feeding will always raise the feed-dog tothe same elevation.

With the above and other objects in view, as will hereinafter appear,the invention comprises the devices, combinations, and arrangements ofparts hereinafter set forth and illustrated in the accompanying drawingsof a preferred embodiment of the invention, from which the severalfeatures of the invention and the advantages attained thereby will bereadily understood by those skilled in the art. In the drawings,

Fig. 1 is a vertical sectional view of a portion of a sewing machineembodying the invention,

Fig. 2 is a bottom plan view of the portion of the sewing machine shownin Fig. l, and

Fig. 3 is a perspective view, as seen from above, of certain of theelements illustrated in Figs. 1 and 2.

In the embodiment of this invention selected for illustration, thenumeral ll indicates the substantially rectangular bed-plate or base ofthe sewin machine providing on its upper side a work-supporting plate l2and having, formed integral with its under side, downwardly extendll'lgfront and rear walls I4 and I6, and end walls I! and is, forming abox-like enclosure, of which the downwardly facing opening is normallyclosed by a bottom cover-plate 19 held in place by a nut (not shown).

An upstanding hollow standard 2| rises from the bed H and at its upperend the standard carries an overhanging bracket-arm (not shown) of whichthe free end carries the usual reciprocatory needle-bar 24 and thepresser-bar 25.

The bracket-arm rotatably supports an unshown main drive-shaft whichoperates the reciprocatory needle-bar 24, in a known manner, and thissame drive-shaft in a manner shown and '2 described in patentapplication of Wilbur J. Peets, Serial No. 774,597, filed September 17,1947 (now Patent No. 2,617,375), drives a loop-taker shaft 21, which inturn drives a loop-taker 28 arranged to cooperate with a suitablethread-carrying needle 29 in the formation of stitches. Since thestitch-forming mechanism forms no part of the present invention, furtherillustration and description thereof is deemed unnecessary. If desiredthe stitch-forming mechanism may be constructed and operated in a mannersimilar to that disclosed in the United States patent of Herbert J.Goosman, No. 2,063,841, dated December 3, 1936.

The work-support I2 is provided with a throatplate 3| having feed-slots32 through which operates a serrated feed-dog 34 secured by screws 31 onone end of a long feed-bar 36. At its rearward end, the feed-bar 36 ispivotally connected, as at 38, to the upper end of a pair of feedadvancerockers 39 extendin upwardly from a feed-advance rock-shaft 4| journaledon suitable pintles, of which one is shown at 42. Also, a feed-liftrock-shaft 44 is journaled on pintles, of which one is shown at 43.Suitable oscillatory movements are given to the feed-advance rockshaft4| and the feed-lift rock-shaft 44 by any known means such, for example,as disclosed in Patent No. 2,617,375 supra.

The feed-bar 36 is provided with a depending lug 47, of which the lowerend carries a horizontally extendin pin 48 that pivotally mounts thelower end of an upwardly extending link 49. The upper end of the link 49is pivotally connected by a pin 5| to one arm 52 of a horizontallyextending lever 53, having a central hub 54 freely journaled on thefeed-lift rock-shaft 44. The hub 54 is provided with an annular recess56 concentric with the shaft 44. The recess 56 accommodates a helicalspring 51 havin one end anchored in a hole 58 formed in the lever 53 andhaving its other end anchored in a hole 59 provided in a flange 6!formed integral with the feed-lift rockshaft 44, the flange 6| beinglocated adjacent to one side face of the lever 53 and thus preventingthe lever 53 from movement longitudinally of the feed-lift rock-shaft44. The lever 53 is held from movement in the other directionlongitudinally of the shaft 44, by a spring wire clip 62 seated in agroove in the shaft 44. Another arm 63 of the horizontally extendintwo-armed lever 53 is apertured by a horizontally extendingfunnel-shaped hole or clearance aperture having a cylindrical portion 54and having at its end nearest the wall ll and thus remote from thecrankarm 68, hereinafter mentioned, a concave frustoconical countersinkor seat portion 66 for seating a convex frusto-conical self-centeringmember [2! presently to be described.

It will be noted that the two arms 52 and 63 of the lever 53 extendhorizontally on opposite sides of the feed-lift rock-shaft :44,"the-arm52 extending toward the loop-taker shaft 21 in the front of the sewingmachine bed, and the arm 63 extending toward the feed-advance rock-shaft4| in the rear of the bed. It will also be noted that the lever 53 is ofuniform thickness was measured in the direction of the axis of thefeedlift rock-shaft 44. Also :the-seating-members 66 and I2! are both ofsymmetrical, frusto-conical form, and the cylindrical portion 64and thefrusto-conical portion 66 are concentric.

The hereinbefore mentioned feed-lift rockshaft 44 carries a horizontallyextending crankarm 68 adjacent to and" formed integral with the flange6|. The arm 68 is provided with a horizontally extending cylindricalthreaded h01eB9. In order-to limit the downward movement of the feed-dog34, there is provided a bracket 83, which is held to a boss of the baseII by a screw 82. The bracket 83 has a threadedhole and thereby carriesan adjustable stop-screwt8fi of which the upper end (not'shown) may beengaged by the lower surface of the arm 52. The previously describedmechanism is substantially the same as the mechanism which formed thesubject of the patent application Serial No. 222,616 supra.

The present invention is concerned primarily with a novel and improvedmeans for selectively connecting and disconnecting the integrally formedflange GI and crankarm 08 with the arm vI53 which is apertured by thehole 5486 of which, as stated, one portion 64 is cylindrical andtheother portion 66. is frusto-conical. This connecting means comprises acylindrical stem or screw IOI, of which the major portion is externallythreaded as at I 02. A small head-end portion,i03 of the stem isunthreaded and this head portionI03 is provided with a screw driver slotI04. Athumb-nut I05, having a. knurled head I06 and a shank 127, isprovided with a concentric bore I03. The major portion of the bore I08of the thumb-nut I is internally threaded as at I99, however, theportion H2 of this bore adjacent the head I08 is unthreaded, smooth andcounterbored so that the unthreaded head [03 of the screw vIIlI may, asbest shown in Fig. 2, enter the bore I08 for a short distance. The shankI01 of the nut I65 is split longitudinally by a saw out H3. I05 is alsoprovided with a recessed screw driver slot I I4.

A hollow sleeve H6, having an enlarged end or centering head Ill and astem II 8, is .provided with an unthreaded axial, concentric bore I I9coextensive withthe sleeve. The enlarged end .I I'I-has an outfacingconvex frusto-conical surface or centering member IZI having the sameslope as the concave frusto-conical countersink 66 hereinbeforedescribed. When the threaded portion I22 of the stem IOI is screwed intothe threaded hole 69, as hereinafter described, a lock-nut I24 isscrewed on the end of the stem IOI thus securing the stem IOI to arm 68.With this arrangement, the sleeve H6 is both rotatably and slidablymounted on the screw HM, and the thumb-nut I05, due to the threads I62and I09, may be moved toward or away from the sleeve He, thus making itpossible selectively to seat the frusto-conical centering member I2I in.the countersink 66 or to release the centering member I 2! from thecountersink 66. In this connection it should be noted that, due to theunthreaded head I03 of the screw IOI, the thumb nut I05 cannot beremoved from the head end The head of the thumb-nut the slit H3, theshank I91 of the thumb-nut I05 can be adjusted to hold the thum-nut I05rin any selected position thus assuring that the .out causing movementof the feed-dog 34.

arms 53 and til-68 will either remain connected .or disconnecteddepending on the setting of the thumb nut I05.

The operationof the mechanism is as follows. When it. isdesirable to usethe sewing machine for darning or embroidering, the feed-dog 34 is*depressed below the upper surface of the throat-plate 3| by graspingthe thumb-head I06 and [turning the thumb-nut I05 from the positionshown by'solid lines in Fig. 2 to the position therein shown by dottedlines. This releases the frusto-conicalwentering member I2I from thecountersink 66 and breaks the connection between the arm 63 of the lever53 and the arm I38 of the rock-shaft 44. Since the external diameter ofthescrew Ifll is much less than the internaldiameter of the hole 64, thelever 53 is free to move independently of the feed-lift-rockshaft 44 andits integral arm 68. Under these circumstancesthe spring 51. biases thelever- 53 to turn'clockwise as seen in Fig. 1, until the lower surfaceof the arm .52 of the lever 53 is stopped by the'upper end (not shown)of the screw 06.

This lowers the arnr52, the pin 5i and consequently lowers the link 49,the pin 48 and the depending lug 41, with the result that the feeddog 34is lowered below the upper surface of the throat-plate- 3|. Sincetheconical centering member I2I is disengaged from the countersink t6, thefeed-lift rock-shaft 44, its integral armiifl, and thestem IOI are freeto move with- This freedom of movement is fully described in. thehereinbefore mentionedpatent application Serial No. 222,616.

Whenit becomes desirable to use-the sewing machine to perform ordinarysewing operations, the thumb nut I05 by .means .of the thumb-head I06 isscrewedfromthe dotted position shown .in Fig. 2 to the position shownby'solid lines. .As thisis done, the end IO'Ia of the shank I07 engagesthe end-.IISa of the sleeve H6, and, asthesleevel I6 is pushed forwardby the shank I01, .the. inclined surface IZI of the centering member H6engages the frusto-conical countersink 66 with the result that as thethumb-nut I 05 advances on the screw I 0i, the lever 53 is caused tomove-counter-clockwise (Fig. l) about the shaft 44 against the bias ofthe spring 57, until'the conical flange I2I becomes fully seated in thecountersink 66. This always brings the feed-dog 34 to the proper height,because there is no chance of the member I 2| sticking or bindinguntil'full seating has been attained. When this is achieved, the screwIilI becomes concentric with the hole and the lever 5-3 becomes clampedto the 'arm' 68, the arm 52 of the lever 53 is raised from contact withthe top of the stopscrew 86, and whenever the feed-lift rock-shaft 44oscillates, the lever 53 moves therewith, causing the link 49alternately to lift and lower the feedbar' 36, imparting rising andfalling movements to the feed-dog 34. It should be noted that theconical centering member I2! and the countersink 66 are of such size andshape as to easily and .properly elevate the feed-dog 34 for ordinaryseaming operations when the centering member :IZI is causedto engage theseat 68.

Having thus set forth the nature of the invention, what I claim hereinis:

1. In a sewing machine, a releasable connection for selectivelyconnecting and disconnecting a feed-lift rock-lever with a cranlzlever,each of said levers having a hole and one of said holes being acentering hole, comprising, a threadedstem freely passing through saidcentering hole and fastened into said other hole; a hollow sleeve havingan unthreaded longitudinal bore and a centering head for engaging saidcentering hole, said sleeve being carried on said threaded stem; and athumb-nut screwed on said threadedetem for moving said hollow sleeve.

2. In a sewing machine, a releasable connection for selectivelyconnecting and disconnecting a feed-lift rock-lever having a conicalhole, with a crank-arm. having a threaded hole comprising, athreaded-stem freely passing through said conical hole and screwed intosaid threaded hole; a hollow sleeve having a longitudinal bore and acentering head for engaging said conical hole, said sleeve beingslidably carried on said threaded stem; and a thumb-nut screwed on saidthreadedstem for moving said sleeve.

3. In a sewing machine, a releasable connection for selectivelyconnecting and disconnecting a feed-lift rock-lever having afunnel-shaped hole, with a crank-arm having a threaded hole comprising,a threaded-stem freely passing through said funnel-shaped hole andscrewed into the threaded hole of said crank-arm, a hollow sleeve havingan unthreaded longitudinal bore and a frusto-conical centering head forengaging said funnel-shaped hole, said sleeve being slidably carried onsaid stem; and a split thumbnut screwed on said threaded-stem forengagement with said sleeve.

4. In a sewing machine, a releasable connection for selectivelyconnecting and disconnecting a feed-lift rock-lever having afunnel-shaped hole, with a crank-arm having a threaded hole comprising,a threaded-stein freely passing through said funnel-shaped hole andscrewed into the threaded hole of said crank-arm, said stem having asmooth head provided in its end with a screw-driver slot; a nut lockingsaid stem to said crank-arm; a hollow sleeve having a longitudinal boreand a frusto-conical centering head for engaging said funnel-shapedhole, said sleeve being slidably carried on said stem; a thumb-nuthaving a split portion screwed on said stem for moving said hollowsleeve, said thumbnut having a smooth bore to receive the smooth head ofsaid stem.

5. A feed-dog throw-out mechanism for sewing machines including incombination a rockshaft, a crank-lever carried by said rock-shaft, alever pivoted on said rock-shaft, one of said levers being provided witha conical hole and the other lever being provided with a threaded hole.a feed-dog, means connecting oneof said levers with said feed-dog, and areleasable connection selectively connecting and disconnecting saidlevers, said releasable connection comprising a threaded-stem freelypassing through said conical hole and screwed into said threaded hole, ahollow sleeve having a longitudinal unthreaded bore and a centeringhead, and a thumb-nut screwed on said threaded-stem.

6. A feed-dog throw-out mechanism for sewing machines including incombination a rockshaft, a crank-lever formed integral with saidrock-shaft, a lever pivoted on said rock-shaft, one of said levers beingprovided with a funnelshaped hole and the other lever being providedwith a thread-hole, a feed-dog, means connecting one of said levers withsaid feed-dog, and a releasable connection selectively connecting anddisconnecting said levers, said releasable connection comprising, athreaded-stem freely passing through said funnel-shaped hole and screwedinto said threaded-hole; a hollow sleeve having a longitudinal bore anda frusto-conical centering head, said sleeve being slidably carried onsaid stem, and said centering head adapted to enter said funnel-shapedhole; and a thumb-nut screwed on said threaded-stem.

'7. A feed-dog throw-out mechanism for sewing machines including incombination a rock-shaft, a crank-arm formed integral with saidrock-shaft and said crank-arm being provided with a threaded hole, afeed-dog, a lever pivoted on said rock-shaft and provided with afunnelshaped hole having a cylindrical portion and a frusto-conicalportion concentric with said cylindrical portion, means connecting saidlever with said feed-dogand a releasable connection selectivelyconnecting and disconnecting said lever and said crank-arm, saidreleasable connection comprising, a threaded-stem freely passing throughsaid funnel-shaped hole and screwed into the threaded hole of saidcrank-arm, a nut locking said stem to said crank-arm; a hollow sleevehaving a longitudinal bore and a frustoconical centering head, saidsleeve being slidably carried on said stem; and a split thumb-nutscrewed on said threaded-stem.

8. A feed-dog throw-out mechanism for sewing machines including incombination, a rockshaft, a crank-arm formed integral with saidrock-shaft and said crank-arm being provided with a threaded hole, afeed-dog, a lever pivoted on said rock-shaft and provided with afunnelshaped hole having a cylindrical portion and a frusto-conicalportion concentric with said cylindrical portion, means connecting saidlever with said feed-dog, a releasable connection selectively connectingand disconnecting said lever and said crank-arm, said releasableconnection comprising, a threaded-stem freely passing through saidfunnel-shaped hole and screwed into the threaded hole of said crank-arm,said stem having a smooth head provided with a screw-driver slot; a nutlocking said stem to said crank-arm; a hollow sleeve having alongitudinal bore and a frustoconical centering head, said sleeve beingslidably carried on said stem; a thumb-nut having a split portionscrewed on said stem and a smooth bore to receive said smooth head ofsaid stem.

9. In a sewing machine, a releasable connection for selectivelyconnecting and disconnecting a feed-lift rock-lever with a crank-lever,each of said levers having a hole and one of said holes being acentering hole, comprising a stem freely passing through said centeringhole and having one end securely fixed into said other hole; a hollowsleeve having an unthreaded longitudinal bore and a centering head forengaging said centering hole, said sleeve being slidably carried on saidstem; and a thumb member turnable on the free end of said stem andarranged to move said sleeve lengthwise on said stem.

References Cited in the file of this patent UNITED STATES PATENTSNiunber Name Date 1,879,191 Goosman Sept. 27, 1932 1,908,292 Grieb May9, 1933 2,496,817 Schulthess Feb. 7, 1950

